A Home NodeB (HNB) network architecture is under development now. In this architecture, a UE (User Equipment, User Equipment) uses authorized spectrum and a generic Internet Protocol (IP) access network such as DSL (Digital Subscriber Line, Digital Subscriber Line) and Cable Broadband (Cable Broadband) to get connected to a mobile network of an operator through a home Wireless Access Point. The authorized spectrum may be spectrum used by wireless access networks such as UTRAN (UMTS Terrestrial Radio Access Network, UMTS Terrestrial Radio Access Network), E-UTRAN (Evolved UTRAN, Evolved UTRAN), CDMA (Code Division Multiple Access, Code Division Multiple Access) network, WiMAX (Worldwide Interoperability for Microwave Access, Worldwide Interoperability for Microwave Access) network, and WLAN (Wireless Local Area Network, Wireless Local Area Network). In the HNB network architecture, the HNB (Home NodeB, Home NodeB) is connected to an HNB GW (Gateway, Gateway), and the HNB GW is connected to an SGSN (Serving GPRS Support Node, Serving GPRS Support Node). The HNB GW provides the convergence function and prevents too many HNBs from accessing the SGSN directly so as to avoid too much load onto the SGSN. The SGSN is a mobility management element. In other systems, the SGSN may be an MME (Mobility Management Entity, Mobility Management Entity), WiMAX AGW (Access Gateway, Access Gateway), and so on.
In the prior art, when the UE hands over from a source base station to a target base station, the source base station transmits information about bearers, which involve data forwarding, to the target base station transparently through the MME. The target base station prepares resources for all bearers of the UE and the bearers that involve data forwarding, and then the UE starts handover.
In the process of implementing the present invention, the inventor of the present invention finds at least the following defects in the prior art:
When a local breakout (local breakout) service exists on the UE, according to the foregoing procedure, a bearer is set up again on the target base station in the handover process. However, the local breakout service requires no service continuity, and setting up the bearer on the target base station again leads to waste of resources. A local breakout service is a service in which the UE accesses the Internet directly through an HNB or HNB GW instead of the traditional mode of accessing the Internet through an HNB, HNB GW, SGSN, and GGSN (Gateway GPRS Supporting Node, Gateway GPRS Supporting Node), so as to reduce mobile core network resources consumed by the Internet traffic. The local breakout service is not sensitive to Quality of Service (QoS), and does not need to keep service continuity. More importantly, after the UE hands over to the target base station, the IP address allocated by the HNB or HNB GW to the UE for the local breakout service cannot be sustained, and it is not necessary to keep on the local breakout service. Moreover, because the IP address for the local breakout service is not available any longer, errors of routing traffic of the UE will occur, and packets will be lost.